Power generating and distributing system.



. A. c. EASTWOOD.

POWER GENERATING AND DISTRIBUTING SYSTEM.

APPLICATION FILED MAY 7, 1908.

930,363, v Patented Aug. 10,1909.

WB'I'N E 5 55 5 t AT'I'OP-N EY -whiehthe:following is a specificat on.

ARTHUR c. EASTWOOD,

or CLEVELAND, onro.

POWER GENERATING AND'DIS'IRIIB'UTING SiSTEM.

Nos 930,368.

Specification of Letters'Patent.

mama Aug. 10, 1909.

. Application filed May 7, 1908: Serial No. 431,478.

To all whom it may concern:

Be it known that -I, ARTHUR C. EAs'rwooD, a citizen of the UnitedStates, residing at Gleveland, in the county of Cuyahoga and,

State ofOhio, have invented or discovered new and useful Improvements inPower- Generating and Distributing Systems, :of.

My invention relates to the generation and distribution of power inmetallurgical Works, particularly-in works devoted to the manu factureof iron and steel. w

The objects of my invention are first, to

' generate power at maximum efficiency; sec-- 0nd, to distribute andutilize power at maximum efficiency and minimum cost; third, to apply touseful purposes heat en- .ergy which is at present wasted inmetallurgical works; fourth, toprovide a dry blast for blast furnaces,thereby reducing the amount of heat required to heat the blast and alsoreducing the fuel consumption in the furnace; and fifth, to provide apower generating and distributing system which can readily be applied toexisting plants without excessiveexpense and witha large saving in fuel.v

It has been demonstrated that the waste gases from a blast furnace canbeefiieiently used as fuel in a gas engine and that a blast furnace willordinarily emit sufficient gas not only to provide power for com ressingair for its own blast but there wil be a very large surplus of gas whichmay be used for generating power for other purposes. 7 In ametallurgical-plant, embracing not only a. blast furnace or furnacesbut'also mills for; finishing the product, the surplus gas may :beefficiently used in'generating .power'for carrying on the finishingprocesses, particularly in driving the mills for rolling the productinto the required shapes. In the' -majority of existing plants the'finis'hing mills are driven by steam engines, 'fre uently of severalthousand horse-power, w ich of-course *entail a heavy expense'for fuel.

Where gas englnes have been installed to' 'convert into power thesurplus Waste gases from the'blast furnace, so far asI am aware, theyhave invariably been used to driveelectric generators which in turnfurnish ower for the various finishing machinery. f leetric power is,o'feourse, ideal for cranes, con'veyers and like machinery and is also.particularly applicable to large motors wa engines may ning constantlyin a givendirection. Particular difficulty, however, is met with in 4applying electric ower to the driving'of reversing mills, w i'chordinarily require a very large amount of power and which must be freuently andrapidly reversed. The electrica equi ment for this purpose,

. as at present deve oped, is excessively expensive, somewhatcomplicated and its satisfactoryioperation is yet somewhatproblematical.

On account of the cat cost of the electricalequipment and t e fact thatto apply it steam engines of pprhaps several thousand horse-power must ethrown out of service, the utilization of waste blast furnace gas inmost existing plants becomes prohibitive. By means of my invention thesedifficulties are overcome. Power derived from the com bustion of s'urlusblast furnace gas in gas e utilized for driving the heaviestreversing mills, and this without excessive cost or complication. Infact, the steam engines now in place for driving such mills in existingplants can be utilized to advantage. Again it has been found in racticethat a blast furnace will operate witfi a con.- sumption of less fuel indry cold weather than that required when the air is more heavily ladenwith moisture and that considerable saving in fuel has been realized byartificially removing moisture from the blast delivered to the furnace.

My invention embraces means whereby moisture can be removed from theblast with exceptional economy and with a minimum amount of additionalor auxiliary apparatus. In carrying-out my invention I provide gas orinternal combustion-engines adapted to use Waste-gases from the blastfurnace as fuel. The gas engines are arranged to drive air compressors,compressing air preferably in two or more stages, the first stagepreferably bringing the air to the maximum pressure required in blowingthe furnace, which, in accordance with present practice, would be aboutthirty pounds gage pressure per square inch. l he compression is carriedon isothermally as far as practicable, inter-coolers being providedbetween the stages. The final stage of compression preferably brings theair to Working pressure, say 150 to '200 pounds per squareinch. Incases, however, In which thewcompressed air must be'transmitted 'toconsiderable distances it may be compressed and transmitted at a higherpressure-and this pressure reduced at the point I provlde reheaters forheating the air before use in the mill-engines. At the millssoaking-pits or heating furnaces are customarily provided for bringingthe iron or-steel to the requisite temperature before rolhng. Owing tothe high degree of heat required, the gases of combustion, after heatingthe its or furnaces, are, customarily liberate into the stack at a hightemperature. "In carrying out my invention I preferably use the" gasesof combustion from the soaking pits or heating furnaces to reheat thecompressed air. In existing plants where the mllls have been driven bysteam engines the bollers'may be used as reheaters, their ca acityserving as a reservoir or receiver for t e compressed air. As can bereadily demonstrated, the proper reheating of the air will permit ofrealizin approximately double the power which coul be developed withoutreheating. Not only can the normal losses of transmission be made up butmore ower can be developed than has actually; geen expended incompressing the air. T e heat absorbed in the process of reheating maybe converted into mechanical work at a very high efficienc and, in usingfor the purpose heat which 1s ordinarily wasted, I provide means forsecuring a large augmentation of power at a trifling cost. I

For drivin the mills I provide compressed air engines qrlwhich purpose,in existing mills, the present steam-engines may be employed,thus'making it possible to realize the advantages of using sur lusblast-furnace gas for power purposes wit out excessive alteration orcost of installation.

In the case of continuously running mills, such as threc high mills, thecompressed air may be used expansively. Preferably the engine will becom ound and the air reheated. before entering fhe hi h pressurecylinder and again reheated be ore assing into the low pressurecylinder. In-t e case of reversing nulls such as blooming-mills, wherelarge variations in speed as well as frequent reversals are required theengine must be overned by throttle as well as by cut-off. iin such casesI provide a return or exhaustline from the engine to the blast-furnacesand utilize the exhaust from the engine for furnishing the blast for thefurnaces, the exhaust being I passed through a reducing valve to bringit to the requisite blast pressure.' 4

In ap lying my invention to' existing plants w ere steam engines are tobe converted into air engines a by-pass will be provided, by means ofwhich the engine ma be permitted to exhaust into the atmosp ere and bethus relieved of back pressure at times when the maximum power of theengine is required.

At or near the blast-furnaces I provide a 'in' the first stage ofcompression, which, as

previously noted, will be preferably at the maximum pressure requiredfor the blast.

To remove moisture from the blast, I take a portion of the hi h-pressureair, and ermit it to expand adia atlcally in a cylindbr behind a istonwhich may be arranged to assist in t e compression of further an or maybe arranged to perform other useful work, such for instance as drivingan electric gen erator. I expand the air in this way to a point at orslightly above the maximumblast pressure and then exhaust it'into theair for the blast. The adiabatic expansion of the air reduces it to alow temperature and by exhausting this air into and therefore mixing itdirectly with the blast, the blast is effect- 'which it carries may thenbe condensed.

This condensed moisture I separate from the -air by suitable'means,'suchas a centrifugal separator.

Since the refrigerating agent is exhausted directly into the blast andadds to the volume of the blast the cooling action will beefl'ectivc'owing to the intimate commin ling of the cold air exhaustwith the blast and the efficiency will be high since the exhaustperforms useful work in assisting in blowing the furnace.

In the accompanying drawing I have illustrated my inventiondiagrammatically since the invention does not relate to the details ofthe apparatus employed.

In the drawin B is a blast furnace. The gases emitted from thefurnaceare led through the pipe 1) to the dust-catcher D, in which the dust isremoved from the gas. The gas is then conveyed through the pipe g to thecylinders g and g of a gas engine G and serves as fuel for the en ine.

receiver of the requisite capacity for storing 4 pressed in more thantwo stages if necessary.

I is an inter-cooler through which theair passes between the stages ofcompression.

' the inter-cooler the heat due to the compression is removed by wateror other cooling agents so as to render the compression as nearlyisothermal as possible.

From the high pressure cylinder, C, the air passes to a receiver It. Apipe line I is connected to the receiver andserves to conduct thecompressed air to the points of use. In the diagram I have shown thepipe-line extending to a mill-engine E driving a finishing mill M. F isa soaking" pit or heating furnace used for bringing the iron or steel tothe proper temperature for rolling. The gases of combustion from thefurnace F are conducted to a reheater Hf in which they pass throughsuitable tubes or flues. The gases are then conducted through similar Itubes or flues ina second reheater H and then pass into the air throughthe stack 71. The compressed air before entering the high pressurecylinder E of the engine E passes through the reheater H The exhaustfrom the high pressure cylinder E passes through the reheater H beforeentering the low pressure cylinder E The exhaustfrom the low pressurecylinder E passes through the pipe P to the receiver R v V is a reducingvalve-through which the air passes before entering the receiver B A isan air engine which I have indicated as driving an electric generator GThis generator may furnish current for operating electric cranes,conveyin tables and other machinery used in hand ing and finishing theproduct of the blast-furnace. Compressed air after working expansivelyin the cylinder of the engine A is exhausted into the receiver R Thisexhaust, dueto adiabatic expansion, will be at a low temperav .tureand-will chill the air in the receiver which it carries to condense. Thecondcnscd moisture is removed by a separator S.

V is a regulating valve through which the blast passes to the stoves U,in which it is heated before entering the furnace through the twyers T.

'mill-engines is'not available for furnishing the requisitel'ilast forthe furnaces.

causing a large portion ofethewater vapor V is. a relief valve in theexhaust pipe-I, from the-engine E which may be opened,.

permitting the exhaust to escape into the atmosphere at times when themaximum power of the engine is required.

I claim 1. In a metallurgical plant, a blast-fur-- nace, a gas-enginearranged to use the waste gas from the blast-furnace for fuel, anaircompressor driven by the compressor driven by the gas engine, a mill,a compressed air engine for driving the mill, and means for leadin theair from the compressor to the air engine for the operation of thelatter.

2. In a metallurgical plant, a finishing mill,

a compressed air engine for driving the mill,

a heating furnace, an air heater in the path of the compressed air toair engine, and.

means for leading the waste gases of said heating furnace to the airheater.

. '3. In a metallurgical plant, a blast-furnace, a gas-en ine arrangedto use the waste gas from the last-furnace for fuel, an aircompressordriven by the gas-engine, a mill, acompressed air engine for driving themill, means for leading the air from the compressor to the air-enginefor the operation of the latter, a heating furnace, an air heater inthe-path of the compressed air to the air-eninc, and means for leadingthe waste gases from said heatin furnace to the air heater.

4. In a'metallurgic'al plant, a blast-furnace, a gas engine arranged touse the'waste gas from the blast-furnace for fuel, an air as engine,means for leading the compressed air to the blastfurnace for blowing thesame, mechanism for treating the product of. the blast-furnace, and

a compressed air en inc operatively connected to said mechamsmandderiving compressed air from the compressor.

5. In a metallurgical nace, an air engine driven y compressed air, andmeans for leading the exhaust of the engine to the blast-furnace forblowing the same.

6. In a nace, a gas-engine arranged to use the waste gas from theblast-furnace for fuel, an aircompressor driven by the gas-engine, amillengine actuated by air from the compressor, and means for leadingthe exhaust of the engine to the blast-furnace for blowing .the

same. V

7. The combination of a blast furnace, a gas engine arranged to use thewaste gas from. the blast furnace for fuel, an aircompressor driven bythe gas engine, a mill,a

metallurgical plant, a blast-fur' lant, a blast-furreversing compressedair engine connected for driving said mill, and means connecting II. M.DIEMER, (I. PIRILE.

